Schedule a workflow from a list

Question

I am using a calendar list to send notifications, currently I have it working to send a notification 90 days before the renewal date and 70 days before the renewal date. I am achieving this by using "start workflow", then fx "set contract status" with the options active, pending renewal and cancelled. Then delay until notification date, which pulls from the list column "start date" + "days to add" (manual input). "Run if" status is/or active or pending renewal. Then Notification email goes out.

Then the process starts over -> start workflow -> set contract status -> delay until "notification date2" which is calculated by "start date" + "days to add2" -> "run if" contract status is "active" or "pending renewal".

My question is how do I automate this workflow to repeat for the same event next year, if it repeats? I am using sharepoint 2013 and SPARKnit.

Thanks!